Effect of camptothecin on the activation,proliferation and cell cycle distribution of the mouse T lymphocytes in vitro

AIM:To study the effects of camptothecin(CPT) on the activation,proliferation and cell-cycle distribution of the mouse T lymphocytes stimulated by concanvalin A(ConA) in vitro.METHODS:A model of T cell activation and proliferation was established by stimulated the cells with Con A.T cells were treated with different concentrations of CPT.The expression of CD69,the early marker of CD3+ T cell activation,was measured by FACS.The proliferation index was determined by carboxyl fluorescin diacetate succinmidyl ester by flow cytometry.The cell-cycle distribution was analyzed by propidium iodide staining.RESULTS:After stimulation with Con A for 6 h,the activation rate of CD69+ T cell in Con A group was(58.88±0.55)%.The percentages of CD69 positive cells were(55.48±0.98)%,(54.67±1.05)%,(50.40±0.82)%,(42.47±1.32)%,correspond to the treatments with different concentrations of CPT(10 nmol/L,20 nmol/L,50 nmol/L,100 nmol/L),respectively.After 48 h treatment with Con A,the proliferation index in different concentrations of CPT treatment(10 nmol/L,20 nmol/L,50 nmol/L and 100 nmol/L) exerted a definite inhibitory effect on the proliferation(P0.01).Moreover,the cell-cycle distribution analysis showed that apoptosis peak was observed in different concentrations of CPT treatment after 48 h cultured with Con A.CONCLUSION:CPT significantly inhibits the early stages of the Con A-induced T cell activation and proliferation,and detents the T lymphocytes in G0/G1 phase.